Fruit Pest News

Volume 7, No. 13  June 7, 2006

A weekly, online newsletter whose goal is to update Extension agents and growers of commercial tree fruit and small fruit crops

on diseases and insects in Tennessee.

 

Text appearing in blue or red can be clicked to link to other web sites. Be aware that much of the linked information is produced in other states and may not be applicable to Tennessee.


In This Issue:

 

    1. Tomato and Potato: New Fungicide

    2. Tomato: Timber Rot

    3. Grapes: Botrytis Bunch Rot

    4. Bagworms and Japanese Beetles

    5. Pheromone Trap Catches and Biofixes


1. New Fungicide for Tomato and Potato

Evito (fluoxastrobin) is a new strobilurin fungicide that has received federal registration for several vegetable crops. Produced by Arysta LifeScience, Evito is labeled for potatoes and tuber vegetables, petiole subgroup of leafy vegetables, and fruiting vegetables. Crops grown in Tennessee that are included in the label are potato, sweetpotato, tomato, pepper, and eggplant. Evito will provide control of early blight and suppression of late blight. Southern blight is also included. As a strobilurin (QoI) fungicide, resistance management will be important. Evito should be rotated with products with different modes of action and the total number of applications should be limited. (SB)


2. Timber Rot of Tomatoes

Sclerotinia timber rot usually appears at this time of year. It is characterized by wilting and a light brown stem rot, either at the soil line or some distance above the ground. Under moist conditions, a white mold forms on the stem surface. A lengthwise slice up the stem shows internal hollowing, white mold, and black, elliptical sclerotia.

Timber rot is an early-summer disease and will run its course soon. In the meantime, you may wish to spray with a specialized fungicide, but the choice is limited. Endura is the best tomato fungicide for Sclerotinia control, but availability seems to be a problem. Quadris is the second choice, if Endura cannot be found. Endura is limited to two applications per season, and Quadris must be alternated with non-strobilurin fungicides. (SB)


3. Botrytis Bunch Rot of Grape

Bunch closing, the time when the berries start to touch, is coming soon for most varieties. A Botrytis fungicide should be applied before bunch closing on tight-clustered French hybrids such as Vignoles and Seyval, and most vinifera varieties, especially Pinot Noir, Riesling, and Chardonnay. Also, removal of leaves around clusters before bunch closing has been shown to reduce losses to Botrytis, by improving the drying conditions in the cluster.

The lineup of bunch rot fungicides has become impressive. It includes Rovral, Vangard, Elevate, Endura, and Scala. Endura has powdery mildew activity, but the others are effective only against Botrytis. You need to apply other appropriate fungicides for control of black rot, bitter rot, the mildews, etc., all of which will continue to be active throughout the summer. It is also important to remember that these Botrytis fungicides are prone to resistance development in the pathogen population. It is therefore recommended that none of these materials be used more than 3 times per year. The Vangard label limits its use to 2 applications per year, at the 10 oz/A rate). Try to use 3 products for Botrytis control, and alternate them. (SB)


4. Bagworms and Japanese Beetles

Bagworms have hatched and moved onto the foliage to feed. When they first emerge and start feeding on the foliage, they produce many small holes in the foliage of blueberries, peach and many other plants. Insecticide sprays for Japanese beetles and various caterpillars will control bagworms.

Japanese beetle adults are starting to emerge and they feed between the leaf veins which gives the leaf a lace-like or skeletonized appearance. They also can feed on the fruit of blueberries, black berries, and raspberries. Japanese beetles have been expanding their range into Middle and West Tennessee in recent years. They tend to aggregate on host plants to feed and mate. The longer that they are allowed to feed on a plant, the more they attract other Japanese beetles to feed and mate. If possible, manage these pests before they become too numerous. Multiple insecticide applications, applied at 3 to 7 day intervals, may be required when Japanese beetles are abundant. On blackberries and raspberries, protect plants from Japanese beetles with carbaryl (Sevin) which has a 7 day preharvest interval (PHI) on brambles. On blueberry, treat with Sevin (7 day PHI) or Provado 1.6F (3 day PHI). On bunch grapes, treat with Sevin ( 7 day PHI), malathion (3 day PHI), Imidan 70 WP (14 day PHI), or Pyrellin EC (12 hour PHI). (FH)


Pheromone Trap Catches and Biofixes

Nashville (Davidson County) Pheromone Trap Catches for 2006
Oriental fruit moth (OFM), redbanded leafroller (RBLR), obliquebanded leafroller (OBLR), codling moth (CM), grape berry moth (GBM), variegated leafroller (VLR), black cutworm (BCW), diamondback moth (DBM)

OFM RBLR OBLR CM GBM VLR BCW DBM
3-1 (put out RBLR, OFM, VLR traps) -- 0 -- -- -- -- -- --
3-2 -- 3* -- -- -- -- -- --
3-9 -- 15 -- -- -- 0 -- --
3-13 0 50 0 -- -- 0 -- --
3-21 0 71 0 -- -- 0 -- --
3-28 0 15 0 -- -- 0 -- --
3-29 (put out GBM, BCW, & DBM traps) 0 5 0 -- -- 0 -- --
3-30 0 4 0 -- 0 0 0 2**
4-4 24*** 34 0 -- 0 0 0 2
4-6 5 14 0 0 1 0 0 1
4-7 14 4 0 0 3**** 0 0 0
4-11 12 10 0 0 1 0 0 1
4-17 39 9 0 0 23 0 0 4
4-18 6 0 0 0 1 0 0 0
4-24 49 0 14^ 0 2 0 0 3
4-27 9 0 15 0 0 0 0 4
5-3 13 0 25 0 0 0 0 1
5-9 10 1 22 0 0 0 0 0
5-19 5 10 27 0 0 0 0 0
5-31 25 12 5 0 0 0 0 6
6-5 9 0 4 0 0 0 0 2

* Biofix for RBLR in Davidson County was March 2.
**Biofix for DBM in Davidson County was March 30.
***Biofix for OFM in Davidson County is estimated to be April 3.
****Biofix for GBM in Davidson County was April 7.
^Biofix for OBLR in Davidson County was April 24.


Bradley County Pheromone Trap Catches for 2006

OFM CM
3-29 3* 0
4-3 26 0
4-5 0 1
4-10 16 0
4-17 19 5**
4-24 17 17
5-1 17 2
5-8 15 1
5-15 2 0
5-29 13 3

*Biofix for OFM in Bradley County on March 29.
**Biofix for CM in Bradley County on April 13.


Putnam County Pheromone trap Catches for 2006

OFM RBLR OBLR CM VLR
3-21 (put out RBLR & OFM) -- -- -- -- --
3-24 0 0 -- -- --
3-27 0 0 0 0 0
3-31 2** 12* 0 2*** 0
4-2 1 3 0 0 0
4-7 6 23 1 1 0
4-10 1 16 0 0 0
4-15 9 60 6 0 1
4-17 0 13 1 0 1
4-21 3 14 0 0 0
4-28 10 3 2 1 0
5-7 0 0 2 0 3
5-12 0 0 0 0 0
5-21 0 0 18 0 0

*Biofix for RBLR in Putnam County estimated as March 3 (trap not out early enough).
**Biofix for OFM in Putnam county March 31.
***Waiting to verify biofix for CM, catch probably too early.


Obion County Pheromone Trap Catches for 2006

OFM RBLR OBLR CM VLR
3-13 1 49* 0 -- 2***
3-21 0 40 0 0 0
3-27 1 2 0 0 0
4-3 2** 13 0 2**** 0
4-17 1 18 3^ 1 5
4-25 7 0 0 0 4
5-1 4 0 3 0 4
5-15 0 0 1 0 0
5-22 0 1 0 0 0
5-29 0 1 1 0 1

*Biofix for RBLR in Obion County estimated to be on March 3 (trap not out early enough).
**Biofix for OFM in Obion County on April 3.
***Waiting to verify biofix for VLR in Obion County, catch probably too early.
****Waiting to verify biofix for CM in Obion County, catch probably too early.
^Biofix for OBLR in Obion County.

Additional Pheromone Trap Catches in Davidson County for 2006
Sod Webworms (SWW), Armyworm (AW)

SWW AW
4-18 3* 0
4-24 15 4**
4-27 15 1
5-3 16 0
5-9 52 3
5-19 41 0
5-31 22 0
6-5 7 0

*Biofix for SWW in Davidson County for 2006.
**Biofix for AW in Davidson County for 2006.

Knox County Pheromone Trap Catches for 2006
Tufted Apple Budmoth (TABM)

OFM RBLR OBLR CM VLR TABM
5-1 40 15 2 5 0 17
5-10 3 1 3 2 1 8
5-15 10 1 0 3 3 3
6-5 9 43 5 1 13 12

The Fruit Pest News URL is: http://web.utk.edu/~extepp/fpn/fpn.htm

Contacts:

 

Steve Bost, Professor and Extension Plant Pathologist

scbost@utk.edu

 

Frank Hale, Professor and Extension Entomologist

fahale@utk.edu

 

Both authors available at:

615-832-6802

fax 615-781-2568

Plant and Pest Diagnostic Center

5201 Marchant Drive

Nashville, TN 37211

 

Copyright 2006 The University of Tennessee. All rights reserved. This document may be reproduced and distributed for nonprofit educational purposes provided that credit is given to University of Tennessee Extension.

 

Programs in agriculture and natural resources, 4-H youth development, family and consumer sciences, and resource development. University of Tennessee Institute of Agriculture, U.S. Department of Agriculture and county governments cooperating. UT Extension provides equal opportunities in programs and employment.

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